The present invention relates to electrical machines having a rotor and field windings and particularly relates to a locking strip system and methods for anchoring the windings to the rotor.
Conventional electrical machines have rotors that support field windings. These rotors typically have rotor cores with axial slots that receive each turn of the field windings. Wedges are typically used to close the rotor slots to restrain the windings against the centrifugal forces that arise as the rotor spins. There are certain disadvantages to this type of electrical machine construction, e.g., assembly of the windings in the rotor is inefficient. Another type of electrical machine has been proposed and constructed which eliminates many of the disadvantages of those prior conventional electrical machines.
In such newer constructions, preformed modular field windings are installed about the rotor. The rotor has poles with defined pole faces and parallel sides adjacent to the pole faces and a winding module fits over the parallel sides of the poles. The modular field windings include winding support braces axially spaced from one another for holding the winding turns. The winding braces are laterally spaced along the long side of the windings and each brace includes a plurality of windings. The braces collectively hold a nested assembly of windings and the braces and windings are secured to the rotor by a locking mechanism. It will be appreciated that the rotor may support at least a pair of modular windings along opposite poles. Also, the winding braces are fitted to each modular winding prior to its assembly with the rotor. There has, however, developed a need for apparatus and methods for maintaining the modular winding aligned with the rotor.